Thank you for your feedback! The feature of highlighting what’s changed in the presentation has started being deployed to Insider Fast and Insider Slow builds. The rest of the Office 365 subscribers will get the feature in a couple of weeks. See the post below for more information, and keep voting on other things on your wish list!

Decks of 30-200 slides are common. Adding slide level edit information would enable groups to track changes. The "Pick up where you left off" is a start!
A "sort or highlight by Date Modified" would save hours for us. Anyone else?